The aim of this work was to study the number of mast cells and macrophages of the gingival lamina propria in young people in chronic inflammation. as a result of the study, new data were obtained on the distribution of mast cells and macrophages in the gum without inflammation. It is for the first time that the effect of microbial inflammation and laser therapy on resident cells of the connective gingival tissue is studied, those cells are part of the oral mucosal immune system, depending on the age. Gingival biopsy material obtained according to dental indications in patients aged 20–40 years was used in the work. CD68+ macrophages were detected by immunohistochemical method, the number and secretory activity of gingival mast cells were evaluated by staining with toluidine blue. The results of the conducted examinations showed that in parodontitis, the number of macrophages and degranulating mast cells in the connective tissue of the gingival lamina propria increases. the use of a diode laser in chronic parodontitis has an effect on the increase in the number of macrophages and gingival mast cells, but not on the degranulation process of mast cells.

Introduction. Breast cancer in women is a very common malignant tumor. The prognosis of the development and management of the disease depend on the clinical stage and biological subtype of the tumor. The aim of the research was to study immunohistochemical characteristics of sentinel lymph nodes in various molecular and biological subtypes of breast cancer. Materials and methods. We studied 44 lymph nodes of females with a diagnosed breast cancer using histological and immunohistochemical methods. Regional axillary lymph nodes without signs of metastatic lesions were taken into the investigation. Hematoxylin and eosin staining was performed; monoclonal antibodies to S100 protein and cluster of lymphocyte differentiation 4 and 8 were used. We used light microscopy to assess the results. Results. We determined molecular and biological subtypes of breast cancer. In 45.5% of cases (n=20) women were diagnosed with luminal cancer (Lum); in 25% of cases (n=11), with Her2+ variant; and in 29.5% of cases (n=13), with Tr– cancer (triple-negative). A more pronounced expression of S100-positive cells was observed in the paracortical zone of lymph nodes in triple-negative compared with the luminal one. We revealed uneven distribution of СD8+ lymphocytes in various subtypes of breast cancer, with an increase in their area in the following sequence: Lum (18.6%), Her2+ (19.8%), and Tr– (20.1%). The lowest number of СD4+ lymphocytes was found in the luminal breast cancer. The largest number of CD4+ cells was observed in the Her2+ subtype. Conclusion. The research demonstrated no reliable differences in the reaction of various sub-populations of T-lymphocytes in early-stage breast cancer. At the same time, we revealed a reliable increase in the number of intrafollicular S100+ cells that indicates dendrite cells activation in Tr– cancer. Keywords: breast cancer, immunohistochemistry, regional lymph node, cellular immunity, lymphocytes

Introduction. E-cadherin participates in the formation of intercellular junctions and protects the epitheliocytes of the gums from apoptosis and regulates proliferation in them. The effect of a diode laser on intercellular contacts, proliferation, and apoptosis of gum epitheliocytes at various ages remains poorly studied. The purpose of the paper was to conduct a comparative analysis of the proliferative and apoptotic activity of human gingival epitheliocytes and their intercellular interaction in chronic inflammation, as well as in age-related diode laser therapy. Materials and methods.The study included patients with and without periodontal inflammation (30 patients in each group). The subjects were divided into 2 age groups: group I included patients aged 20–40 years, whereas group II – 41–60 years. Each age group was divided into subgroups: the control subgroup (patients without gingival inflammation); subgroup with periodontal inflammation (patients with chronic periodontitis); and subgroup after laser therapy (patients after therapy with 940-nm Prometey diode laser). We performed immunohistochemical studies using monoclonal antibodies to Ki-67, p53, E-cadherin; as well as computer morphometry and statistical data analysis. Results. Periodontitis combines a decrease in the number of both proliferating epitheliocytes and E-cadherin-positive intercellular contacts in the basal and spiny layers of the gum epithelium in both young and mature adults (p=0.00002). Exposure of a diode laser has a positive effect on the proliferative activity of epithelial cells and significantly increases the number of E-cadherin-positive intercellular contacts in the basal layer (p=0.00002), but does not affect the expression of p53 (p=0.9) in the gum epithelium in all age groups. Conclusion. Exposure of a diode laser increases the proliferation/apoptosis index in the gingival epithelium and brings the expression of E-cadherin closer to the control values. Keywords: gingival epithelium, chronic periodontitis, diode laser, Ki-67, p53, E-cadherin

Periodontitis is a disease that progresses with age and contributes to the biological aging of the dentition. One of the reasons for this phenomenon is the aging of human gum fibroblasts. Low-intensity laser therapy stimulates the release of growth factors from fibroblasts and their division. The aim of the study was to determine the number, proliferative activity and apoptosis of gingival fibroblasts in people without signs of periodontal inflammation, with chronic periodontitis and after laser therapy. We used biopsy material obtained for periodontal, surgical, orthopedic and orthodontic indications under infiltration anesthesia in two age groups of patients aged 20–40 and 41–60 years. Cell markers Ki-67 and p53 were detected by immunohistochemical methods, the total number of gingival fibroblasts was estimated by staining with hematoxylin and eosin. The results of the conducted studies showed that the number of fibroblasts in the connective tissue lamina of the gums has age-related features. In young people from 20 to 40 years, the number of fibroblasts in gum preparations is 1,12 times higher than in people aged 41–60 years. Among the reasons for the decrease in the number of gingival fibroblasts is a decrease in their proliferative activity and activation of the proapoptotic p53 protein with age. Chronic periodontal inflammation leads to a significant increase in the number of fibroblasts, regardless of the age of the subjects. Fibroblast proliferation and p53 protein expression were more sensitive to microbial inflammation in patients aged 41 to 60 years compared to younger patients. Three-fold laser exposure had a differentiated modulating effect on the state of the gingival fibroblast population, depending on the age of the patients, the number of gingival fibroblasts was restored to the levels characteristic of healthy people, and this was observed only in the group of young patients. Thus, the number of fibroblasts in the human gingival connective tissue lamina changes with age, under conditions of inflammation and under the influence of a diode laser, which must be taken into account in dental practice.